A member information management system disclosed in Patent Literatures 1 and 2 is known as an Information management system for managing information on members and groups when a group is formed by a plurality of members. In the member information management system of Patent Literature 1, a member information management server having a member information database in which personal information of members is registered registers formation information of a new group of which an administrator is a member who sends request information according to the request information so that the other member can browse the formation information by the other client terminal, receives group participation application information from the other member who has browsed the group formation information, registers information indicating that the other member who has applied for group participation has become a member of the group in the member information database, and registers opening notice information of an event for members of a group in a state in which the opening notice can be browsed by only those who are group members and registers attendance/absence communication information for informing whether members will attend the event or not. This system enables members registered in the member information database to freely create a group and enables members belonging to a group themselves to communicate with other members and manage member information.
In the member in management system of Patent Literature 2, a management server system having a web server that operates a shopping site receives a request for registering a plurality of applicants as one group, registers the plurality of applicants as one group on the basis of the request, registers one of members belonging to a group as an administrator who has the authority to add or remove a member belonging to the group, evaluates a behavior such as the record of a product purchase of each member belonging to the group as a behavior of the group, and notifies each member belonging to the group of the benefit corresponding to the evaluation. This system enables a group configuration to be determined relatively freely according to a statement of an applicant who wants to be registered in the group so that members belonging to the group gain a higher score.